The purpose of this project is to conduct resesearch in statistical methods and computer techniques with particular emphasis on those appropriate to the analysis of data from clinical and diagnostic trials and epidemiological studies of cancer. Many of the problems studied under this project arise from the consultative activities of the Section. In the past year this research has included methodology for evaluating time-dependent covariates such as serial tumor marker data, techniques for comparing treatments in situations where there are multiple responses for each patient, a new non-parametric technique for survival analysis which may be used when the censorship mechanism is not independent of the endpoint, design of experiments for detecting synergism or antagonism between two factors, a new technique for putting confidence limits on the difference of two probabilities in 2 times 2 contingency tables especially valuable for small samples, and investigation of two important aspects of epidemiologic methodology.